The present invention relates to a printer which utilizes thermomagnetic effect in forming a latent image on a magnetic material in which light is used to heat the magnetic material.
In a conventional magnetic printer, image is reproduced on a paper by the steps of forming a latent image on a magnetic recording medium in an imagewisely magnetized state, developing the image with magnetic toner of macromolecular resin containing fine magnetic particles transferring the developed image onto a receiving paper by electrostatic or magnetic method and fixing the image by heat or pressure.
To form the latent image on the medium in such a conventional printer, a magnetic head having recording tracks with adequate gaps is scanned over the medium in two-dimensional directions.
In such printer, it is necessary to maintain scanning conditions such as the interval between scanning lines and the scanning speed of the magnetic head constant, which requires extremely precise driving and controlling mechanisms. Particularly when a plurality of operational modes are employed in which the head is operated at a high speed to shorten the scanning time and the development and the transfer of image are carried out at a low speed, the conventional printer has such a disadvantage that the mechanisms are complicated in their construction.
To eliminate the above disadvantage it has been proposed a magnetic printer with a multi-magnetic head array. This printer employs a multi-magnetic head array in which magnetic recording tracks are arranged corresponding to every picture element rows over the entire width of the image. In order to satisfy the preferable resolution of the image to be reproduced, fine recording tracks, each of which has a width less than approx. 100 .mu.m and a track interval of approx. 100 .mu.m must be provided.
However, it is difficult to provide such fine tracks with coil windings corresponding to the respective tracks. Further, there occurs a problem of electromagnetic interference between the adjacent tracks and accordingly it is difficult to perform the reproduction of image with a desired resolution.
On the other hand, it has been proposed a thermomagnetic printer which utilizes thermomagnetic effect. This printer employs a thermal magnetic recording medium whose magnetic properties are affected by the influence of temperature. This recording medium magnetically stores an image by applying a heat to the desired portions of the medium which has been magnetized in advance so as to heat the portions at a temperature higher than Curie temperature, thereby selectively demagnetizing the portions or by applying magnetic flux from the exterior simultaneously upon application of the heat to the medium, thereby selectively magnetizing the heated portions. Such thermomagnetic printer employs as heat applying means a condensed laser light ray, flash light or a heating head array in which a number of resistor heating elements are arranged in one row or a plurality of rows.
However, such conventional thermomagnetic printer has disadvantages that its recording medium is likely to suffer thermal deformation since strong heat energy is applied thereto and that its heat applying means such as laser requires great electric energy.